The PsycINFO database, American Psychological Association's (APA) renowned resource for abstracts of scholarly journal articles, book chapters, books, and dissertations, is the largest resource devoted to peer-reviewed literature in behavioral science and mental health. It contains over 2.5 million citations and summaries dating as far back as the early 1800s. Ninety-eight percent of the covered material is peer-reviewed. The database also includes information about the psychological aspects of related fields such as medicine, psychiatry, nursing, sociology, education, pharmacology, technology, linguistics, anthropology, business, law and others. Journal coverage, which spans from 1887 to present, includes international material selected from more than 2,200 periodicals in more than 27 languages. PsycINFO is indexed with controlled vocabulary from APA's Thesaurus of Psychological Index Terms.